Can i use a short action in a long action stock system?

The Long Action stock will not work with a short action. You can swap the short action chassis between calibres that are short action, but not from short to long or vice versa.

That being said. There are some long action rifles barreled and chambered in what are short action calibres. In these cases, our chassis will still work, but you would need to use a long action magazine to feed the short calibre, which usually results in feeding issues.